Merge #17954: wallet: Remove calls to Chain::Lock methods

48973402d8bccb673eaeb68b7aa86faa39d3cb8a wallet: Avoid use of Chain::Lock in CWallet::GetKeyBirthTimes (Russell Yanofsky)
e958ff9ab5607da2cd321f29fc785a6d359e44f4 wallet: Avoid use of Chain::Lock in CWallet::CreateTransaction (Russell Yanofsky)
c0d07dc4cba7634cde4e8bf586557772f3248a42 wallet: Avoid use of Chain::Lock in CWallet::ScanForWalletTransactions (Russell Yanofsky)
1be8ff280c78c30baabae9429c53c0bebb89c44d wallet: Avoid use of Chain::Lock in rescanblockchain (Russell Yanofsky)
3cb85ac594f115db99f96b0a0f4bfdcd69ef0590 wallet refactor: Avoid use of Chain::Lock in CWallet::RescanFromTime (Russell Yanofsky)
f7ba881bc669451a60fedac58a449794702a3e23 wallet: Avoid use of Chain::Lock in listsinceblock (Russell Yanofsky)
bc96a9bfc61afdb696fb92cb644ed5fc3d1793f1 wallet: Avoid use of Chain::Lock in importmulti (Russell Yanofsky)
25a9fcf9e53bfa94e8f8b19a4abfda0f444f6b2a wallet: Avoid use of Chain::Lock in importwallet and dumpwallet (Russell Yanofsky)
c1694ce6bb7e19a8722d5583cd85ad17da40bb67 wallet: Avoid use of Chain::Lock in importprunedfunds (Russell Yanofsky)
ade5f87971211bc67753f14a0d49e020142efc7c wallet refactor: Avoid use of Chain::Lock in qt wallettests (Russell Yanofsky)
f6da44ccce4cfff53433e665305a6fe0a01364e4 wallet: Avoid use of Chain::Lock in tryGetTxStatus and tryGetBalances (Russell Yanofsky)
bf30cd4922ea62577d7bf63f5029e8be62665d45 refactor: Add interfaces::FoundBlock class to selectively return block data (Russell Yanofsky)

Pull request description:

  This is a set of changes updating wallet code to make fewer calls to `Chain::Lock` methods, so the `Chain::Lock` class will be easier to remove in #16426 with fewer code changes and small changes to behavior.

ACKs for top commit:
  MarcoFalke:
    re-ACK 48973402d8, only change is fixing bug 📀
  fjahr:
    re-ACK 48973402d8bccb673eaeb68b7aa86faa39d3cb8a, reviewed rebase and changes since last review, built and ran tests locally
  ariard:
    Coce Review ACK 4897340, only changes are one suggested by last review on more accurate variable naming, human-readable output, args comments in `findCommonAncestor`

Tree-SHA512: cfd2f559f976b6faaa032794c40c9659191d5597b013abcb6c7968d36b2abb2b14d4e596f8ed8b9a077e96522365261299a241a939b3111eaf729ba0c3ef519b

1 files changed, 73 insertions, 45 deletions

diff --git a/src/interfaces/chain.cpp b/src/interfaces/chain.cpp
index 0b3cd08e22..c8311b2986 100644
--- a/src/interfaces/chain.cpp
+++ b/src/interfaces/chain.cpp
@@ -38,6 +38,21 @@
 namespace interfaces {
 namespace {
 
+bool FillBlock(const CBlockIndex* index, const FoundBlock& block, UniqueLock<RecursiveMutex>& lock)
+{
+    if (!index) return false;
+    if (block.m_hash) *block.m_hash = index->GetBlockHash();
+    if (block.m_height) *block.m_height = index->nHeight;
+    if (block.m_time) *block.m_time = index->GetBlockTime();
+    if (block.m_max_time) *block.m_max_time = index->GetBlockTimeMax();
+    if (block.m_mtp_time) *block.m_mtp_time = index->GetMedianTimePast();
+    if (block.m_data) {
+        REVERSE_LOCK(lock);
+        if (!ReadBlockFromDisk(*block.m_data, index, Params().GetConsensus())) block.m_data->SetNull();
+    }
+    return true;
+}
+
 class LockImpl : public Chain::Lock, public UniqueLock<RecursiveMutex>
 {
     Optional<int> getHeight() override
@@ -65,20 +80,6 @@ class LockImpl : public Chain::Lock, public UniqueLock<RecursiveMutex>
         assert(block != nullptr);
         return block->GetBlockHash();
     }
-    int64_t getBlockTime(int height) override
-    {
-        LockAssertion lock(::cs_main);
-        CBlockIndex* block = ::ChainActive()[height];
-        assert(block != nullptr);
-        return block->GetBlockTime();
-    }
-    int64_t getBlockMedianTimePast(int height) override
-    {
-        LockAssertion lock(::cs_main);
-        CBlockIndex* block = ::ChainActive()[height];
-        assert(block != nullptr);
-        return block->GetMedianTimePast();
-    }
     bool haveBlockOnDisk(int height) override
     {
         LockAssertion lock(::cs_main);
@@ -95,20 +96,6 @@ class LockImpl : public Chain::Lock, public UniqueLock<RecursiveMutex>
         }
         return nullopt;
     }
-    Optional<int> findPruned(int start_height, Optional<int> stop_height) override
-    {
-        LockAssertion lock(::cs_main);
-        if (::fPruneMode) {
-            CBlockIndex* block = stop_height ? ::ChainActive()[*stop_height] : ::ChainActive().Tip();
-            while (block && block->nHeight >= start_height) {
-                if ((block->nStatus & BLOCK_HAVE_DATA) == 0) {
-                    return block->nHeight;
-                }
-                block = block->pprev;
-            }
-        }
-        return nullopt;
-    }
     Optional<int> findFork(const uint256& hash, Optional<int>* height) override
     {
         LockAssertion lock(::cs_main);
@@ -247,26 +234,48 @@ public:
         std::unique_ptr<Chain::Lock> result = std::move(lock); // Temporary to avoid CWG 1579
         return result;
     }
-    bool findBlock(const uint256& hash, CBlock* block, int64_t* time, int64_t* time_max) override
+    bool findBlock(const uint256& hash, const FoundBlock& block) override
     {
-        CBlockIndex* index;
-        {
-            LOCK(cs_main);
-            index = LookupBlockIndex(hash);
-            if (!index) {
-                return false;
-            }
-            if (time) {
-                *time = index->GetBlockTime();
-            }
-            if (time_max) {
-                *time_max = index->GetBlockTimeMax();
+        WAIT_LOCK(cs_main, lock);
+        return FillBlock(LookupBlockIndex(hash), block, lock);
+    }
+    bool findFirstBlockWithTimeAndHeight(int64_t min_time, int min_height, const FoundBlock& block) override
+    {
+        WAIT_LOCK(cs_main, lock);
+        return FillBlock(ChainActive().FindEarliestAtLeast(min_time, min_height), block, lock);
+    }
+    bool findNextBlock(const uint256& block_hash, int block_height, const FoundBlock& next, bool* reorg) override {
+        WAIT_LOCK(cs_main, lock);
+        CBlockIndex* block = ChainActive()[block_height];
+        if (block && block->GetBlockHash() != block_hash) block = nullptr;
+        if (reorg) *reorg = !block;
+        return FillBlock(block ? ChainActive()[block_height + 1] : nullptr, next, lock);
+    }
+    bool findAncestorByHeight(const uint256& block_hash, int ancestor_height, const FoundBlock& ancestor_out) override
+    {
+        WAIT_LOCK(cs_main, lock);
+        if (const CBlockIndex* block = LookupBlockIndex(block_hash)) {
+            if (const CBlockIndex* ancestor = block->GetAncestor(ancestor_height)) {
+                return FillBlock(ancestor, ancestor_out, lock);
             }
         }
-        if (block && !ReadBlockFromDisk(*block, index, Params().GetConsensus())) {
-            block->SetNull();
-        }
-        return true;
+        return FillBlock(nullptr, ancestor_out, lock);
+    }
+    bool findAncestorByHash(const uint256& block_hash, const uint256& ancestor_hash, const FoundBlock& ancestor_out) override
+    {
+        WAIT_LOCK(cs_main, lock);
+        const CBlockIndex* block = LookupBlockIndex(block_hash);
+        const CBlockIndex* ancestor = LookupBlockIndex(ancestor_hash);
+        if (block && ancestor && block->GetAncestor(ancestor->nHeight) != ancestor) ancestor = nullptr;
+        return FillBlock(ancestor, ancestor_out, lock);
+    }
+    bool findCommonAncestor(const uint256& block_hash1, const uint256& block_hash2, const FoundBlock& ancestor_out, const FoundBlock& block1_out, const FoundBlock& block2_out) override
+    {
+        WAIT_LOCK(cs_main, lock);
+        const CBlockIndex* block1 = LookupBlockIndex(block_hash1);
+        const CBlockIndex* block2 = LookupBlockIndex(block_hash2);
+        const CBlockIndex* ancestor = block1 && block2 ? LastCommonAncestor(block1, block2) : nullptr;
+        return FillBlock(ancestor, ancestor_out, lock) & FillBlock(block1, block1_out, lock) & FillBlock(block2, block2_out, lock);
     }
     void findCoins(std::map<COutPoint, Coin>& coins) override { return FindCoins(m_node, coins); }
     double guessVerificationProgress(const uint256& block_hash) override
@@ -274,6 +283,25 @@ public:
         LOCK(cs_main);
         return GuessVerificationProgress(Params().TxData(), LookupBlockIndex(block_hash));
     }
+    bool hasBlocks(const uint256& block_hash, int min_height, Optional<int> max_height) override
+    {
+        // hasBlocks returns true if all ancestors of block_hash in specified
+        // range have block data (are not pruned), false if any ancestors in
+        // specified range are missing data.
+        //
+        // For simplicity and robustness, min_height and max_height are only
+        // used to limit the range, and passing min_height that's too low or
+        // max_height that's too high will not crash or change the result.
+        LOCK(::cs_main);
+        if (CBlockIndex* block = LookupBlockIndex(block_hash)) {
+            if (max_height && block->nHeight >= *max_height) block = block->GetAncestor(*max_height);
+            for (; block->nStatus & BLOCK_HAVE_DATA; block = block->pprev) {
+                // Check pprev to not segfault if min_height is too low
+                if (block->nHeight <= min_height || !block->pprev) return true;
+            }
+        }
+        return false;
+    }
     RBFTransactionState isRBFOptIn(const CTransaction& tx) override
     {
         LOCK(::mempool.cs);